We’ve known for years that breastfeeding lowers the risk of cot death, but a new study from America has given us a better idea of just how ­powerful breastfeeding is as a ­protection against SIDS (sudden infant death syndrome).

In the US, about 3,700 babies died suddenly and unexpectedly in 2015, the most recent year for which data is available. Around 1,600 were identified as cot deaths.

In the UK, just under 300 babies die suddenly every year. Cot death is the leading cause of death among babies between a month and a year old.

The risk of sudden infant death syndrome is cut by almost half if mums breastfeed their child (Image: PA)

Most cot deaths happen during the first six months of life. Infants born prematurely or with a low birth weight are at greater risk. SIDS also tends to be slightly more common in boys.

Two months of breastfeeding, however, cuts babies’ risk of cot death almost by half, and the longer ­breastfeeding continues the greater the protection.

Dr Kawai Tanabe, of Virginia University, US, a leader of the new study, said: “These results are very powerful. Our study found babies who are breastfed for at least two months have a significant reduction in their risk of dying from SIDS. Breastfeeding is beneficial for so many reasons, and this is really an important one.”

Another important finding is that breastfeeding need not be exclusive to offer protection – partial breastfeeding confers the same benefit.

This will come as a relief to mums who can’t manage the WHO -backed aim to breastfeed their babies exclusively for six months.

In the UK, just under 300 babies die each year from cot death (Image: PA)

Study leader Professor Ern Hauck said: “The other important finding from our study is that any amount of breastfeeding reduces the risk of SIDS.”

For financial reasons, many mums have to return to work a few months after the birth of a new baby, so this is reassuring and liberating news for them.

The new research pooled data from eight major studies across the world, involving 2,259 SIDS cases and 6,894 infants where death did not occur.

The size of the study means the results are reliable, despite differing cultural backgrounds.

Though the cause of SIDS remains a mystery, the NHS says parents can reduce the risk by not smoking while pregnant or after the baby is born, and always placing the baby on their back when they sleep.

The myriad health benefits for breastfeeding include reducing the risk of infections, diarrhoea and vomiting, childhood leukaemia, Type 2 diabetes, obesity and cardiovascular disease in adulthood.